I've learned that heptane is used to clean containers (beakers, flasks) in chemical laboratories;
have any of you seen it used safely on auto glass ? It'll probably have to be diluted for such use, and I guess you wouldn't want to spray it on the window since it might get on the paint or rubber. I've tried Eagle 1 20-20 and I still get this greasy buildup on the windows that makes things really ugly in light rain and at night.

lookin' forward to the replies,
-K. '99 A4 1.8tqMS

(1) heptane is a solvent, yes. Therefore it will clean stuff, yes. However, it will definitely dissolve wax on your paint...possibly mar your clear coat, too. It will leach out any oils or silicones in your rubber, probably turning it whitish...Black Again might fix that tho'.

(2) You can't dilute it with water, if that is what you are thinking. Heptane is C7H16...a hydrocarbon. It forms two liquid phases in water (it is insoluble). You could dilute it with Isopropyl Alcohol, since they are miscible, but in my opinion, IPA alone would be just as effective, but without the drawbacks of a alkane cleaner.

For reference, heptane and hexane are used because Benzene causes cancer. Benzene was the glassware cleaner(and dry cleaning fluid) of choice for years, because it is such an excellent solvent. However, both benzene and heptane are overkill for a windshield, IMHO.

s

1st, ammonia based cleaners work well also. It tends to dissolve any aqueous salts that may have deposited (these are hard if not impossible to remove with a pure alcohol cleaner). I think they are not for use on Tinted windows tho'...

2nd, if you are speaking of gunk on your inside windshield, it is quite possible that this is off-gassing solvents from the dashboard and any other vinyl in your car.

So, I would imagine that a first pass with an ammonia based glass cleaner, then a second pass with any non-ammonia based glass cleaner should do the trick.

s

Solution: good old Glass Wax. This stuff is amazing. It micro-polishes the glass and removes every trace of road film normal cleaners won't touch. Its abrasive is cirrium (sp?) oxide, a polish normally used by jewelers. Fear not, it will not damage the glass (unless you apply it with a high speed polisher using too much pressure, in which case it is possible to burn the glass). You won't believe how well you can see through your windshield after you use it. Ideally you should apply it according to directions using a random orbit polisher w/terrycloth bonnet. If your grocery store doesn't have it, try the oldest hardware store in town...if they don't have it make them order it. It's worth the trouble.

I hate that greasy/oily windshield smearing. I tried all products I could get my hands on and
the only thing that seems to remove it is using SoftScrub and elbow grease. You can pickup SoftScrub at any supermarket. I also use newspaper rather then paper towels. This combo seems to really break up that film.

Let me know how it works for you.

Mitch 99.5 1.8tqms

i've hear that straight white vinegar is a very good cleaner, but keep it away from the paint.

...from my local Pep Boys. It looks similar to Soft Scrub. You apply it to a damp sponge and then rub it on the windshield in small overlapping circles. Seems to have done a pretty good job of removing some stubborn road grim/water spots from my windshield. I had been looking for the Bon Ami "Cleaning Powder" that is safe for glass, but it's pretty hard to locate. Here's the info I pulled from their website:

<i>Bon Ami still makes its 1886 formula Cleaning Cake the old-fashioned way – cutting the bars with piano wires and working them by hand. Bon Ami Cleaning Powder is the same 1886 formula but in powder form… and in a rectangular can. Both contain gentle feldspar abrasive for polishing and soap for cleaning all hard surfaces. Use to defog windows and mirrors. NASA even used Cleaning Powder to clean the windows on Skylab.</i>

The normal Bon Ami that you'll find on your supermarket shelf is not safe for use on windows (according to the warning on the back of the can).

Anyway, the RainX glass polish/cleaner (or whatever it's called...sorry, can't remember) seems to work pretty good and it was much easier to locate versus the elusive Bon Ami.

<A HREF="Mailto:andy_hedin@hotmail.com">Andy Hedin</A>
'97 A4 1.8Tqms, Garrett 1.0 Bar, ABT Filter, APR/Borla Exhaust, Euro Headlights, more...

Try Fischer Scientific (880)766-7000 or VWR(630)879-0600.

I'd stay away from heptane for your car, other posters are correct in that it can damage polymers pretty easily.


Hugh
1.8Tqms Avant APR'd, Borla'd

nt

Isn't heptane flammable?

Try a "Miracle Cloth" from Solutions catalog. 1-800-342-9988. Package of 3 for $19.50 + shipping.

Just wet the cloth and wipe the window. No chemicals, no sprays, no bull just use the cloth. It removes all the film, and grunge that builds up on the interior windows. When it gets dirty, you just wash it with soap and water and reuse it.

I'm not affiliated with Solutions, just a happy customer.

early 98 QTip w clean windows